This invention relates to electronics enclosures that are subject to heating from the surrounding environment, such as electronics enclosures that are mounted outdoors and/or exposed to direct sunlight. One problem associated with such enclosures is maintaining the electronics contained within the electronics enclosure at or below a maximum desired operating temperature. This problem has two components; first, the heat input into the electronics enclosure from the surrounding environment, and second, the heat generated by the electronics contained within the electronics enclosure.
With respect to the first component, in some environments, one of the most significant heat loads on an electronic enclosure is the radiant heat load. For example, for many outdoor electronic enclosures, the radiant heat load generated by direct sunlight, often referred to as the solar load, can be quite significant. Conventionally, radiant or solar heat loading has been handled in three ways.
(1) choosing a material for the exterior of the enclosure that is as reflective as possible to the radiant or solar load,
(2) using one or more heat shields to shade the enclosure from direct radiant heating, such as direct sunlight, and
(3) providing a fan for forced air convection cooling of the enclosure.
While each of the above approaches may perform satisfactorily, there is always room for improvement. For example, for some applications, highly reflective materials may not be optimum in terms of the aesthetic appearance of the enclosure, the manufacturing cost of the enclosure, and/or the durability of the enclosure. By way of further example, the use of one or more heat shields can limit flexibility in the aesthetic design of an enclosure, complicate the installation of the electronics enclosure, increase the manufacturing cost and/or limit the amount of cooling air flow over and/or into the enclosure. As yet another example, the use of a cooling fan requires a motor drive and a power supply, which can increase the cost, complexity, size, failure modes, and installation time of the electronics enclosure.
In accordance with one form of the invention, an electronics enclosure includes a first member having a first surface, and a second member having a second surface. The first and second members are movable relative to each other between an enclosing position wherein at least one electronic component is enclosed within an interior chamber of the electronics enclosure and an open position wherein at least one electronic component within the electronics enclosure is accessible for servicing. With the first and second members in the enclosing position, the first and second surfaces face and extend around the interior chamber. The first and second members have third and fourth surfaces, respectively, facing oppositely from the first and second surfaces and defining the exterior of the first and second members, respectively. The electronics enclosure further includes a thermal insulating ceramic coating adhered to and covering a majority of at least one of the first, second, third, and fourth surfaces. The ceramic coating has a thickness on the order of 0.005xe2x80x3 or greater, and includes ceramic particles suspended in a binder.
In one form, at least one of the first and second members is a plastic member, and is preferably a molded plastic member.
In one form, both of the first and second members are plastic members.
In one form, the binder is an acrylic resin.
In one form, the thermal insulating ceramic coating adheres to and covers a majority of the first and second surfaces.
In one form, the thermal insulating ceramic coating adheres to and covers a majority of the third and fourth surfaces.
In one form, the thermal insulating ceramic coating adheres to and covers a majority of the first and second surfaces, and the third and fourth surfaces are not coated with a thermal insulating ceramic coating.